Toddler Limping

My 1 year old just started limping tonight before bed. She would walk around a little bit and it looked fine, but then she’d place her hand on her thigh and limp a little before sitting down. Once she stood up and fell right back down because of it. My husband and I were with her all day and don’t remember anything happening.

Has this happened to anyone before? What was the cause?

We gently squeezed her leg from her thigh down to her toes and she didn’t wince in pain. We can bend and straighten her leg fine too...